Vietnam War, (1954–75), a protracted conflict that pitted the communist government of North Vietnam and its allies in South Vietnam, known as the Viet Cong, against the government of South Vietnam and its principal ally, the United States. Called the “American War” in Vietnam (or, in full, the “War Against the Americans to Save the Nation”), the war was also part of a larger regional conflict (seeIndochina wars) and a manifestation of the Cold War between the United States and the Soviet Union and their respective allies.

At the heart of the conflict was the desire of North Vietnam, which had defeated the French colonial administration of Vietnam in 1954, to unify the entire country under a single communist regime modeled after those of the Soviet Union and China. The South Vietnamese government, on the other hand, fought to preserve a Vietnam more closely aligned with the West. U.S. military advisers, present in small numbers throughout the 1950s, were introduced on a large scale beginning in 1961, and active combat units were introduced in 1965. By 1969 more than 500,000 U.S. military personnel were stationed in Vietnam. Meanwhile, the Soviet Union and China poured weapons, supplies, and advisers into the North, which in turn provided support, political direction, and regular combat troops for the campaign in the South. The costs and casualties of the growing war proved too much for the United States to bear, and U.S. combat units were withdrawn by 1973. In 1975 South Vietnam fell to a full-scale invasion by the North.

The human costs of the long conflict were harsh for all involved. Not until 1995 did Vietnam release its official estimate of war dead: as many as 2 million civilians on both sides and some 1.1 million North Vietnamese and Viet Cong fighters. The U.S. military has estimated that between 200,000 and 250,000 South Vietnamese soldiers died in the war. In 1982 the Vietnam Veterans Memorial was dedicated in Washington, D.C., inscribed with the names of 57,939 members of U.S. armed forces who had died or were missing as a result of the war. Over the following years, additions to the list have brought the total past 58,200. (At least 100 names on the memorial are those of servicemen who were actually Canadian citizens.) Among other countries that fought for South Vietnam on a smaller scale, South Korea suffered more than 4,000 dead, Thailand about 350, Australia more than 500, and New Zealand some three dozen.

Vietnam emerged from the war as a potent military power within Southeast Asia, but its agriculture, business, and industry were disrupted, large parts of its countryside were scarred by bombs and defoliation and laced with land mines, and its cities and towns were heavily damaged. A mass exodus in 1975 of people loyal to the South Vietnamese cause was followed by another wave in 1978 of “boat people,” refugees fleeing the economic restructuring imposed by the communist regime. Meanwhile, the United States, its military demoralized and its civilian electorate deeply divided, began a process of coming to terms with defeat in what had been its longest and most controversial war. The two countries finally resumed formal diplomatic relations in 1995.

French rule ended, Vietnam divided

The Vietnam War had its origins in the broader Indochina wars of the 1940s and ’50s, when nationalist groups such as Ho Chi Minh’s Viet Minh, inspired by Chinese and Soviet communism, fought the colonial rule first of Japan and then of France. The French Indochina War broke out in 1946 and went on for eight years, with France’s war effort largely funded and supplied by the United States. Finally, with their shattering defeat by the Viet Minh at the Battle of Dien Bien Phu in May 1954, the French came to the end of their rule in Indochina. The battle prodded negotiators at the Geneva Conference to produce the final Geneva Accords in July 1954. The accords established the 17th parallel (latitude 17° N) as a temporary demarcation line separating the military forces of the French and the Viet Minh. North of the line was the Democratic Republic of Vietnam, or North Vietnam, which had waged a successful eight-year struggle against the French. The North was under the full control of the Worker’s Party, or Vietnamese Communist Party, led by Ho Chi Minh; its capital was Hanoi. In the South the French transferred most of their authority to the State of Vietnam, which had its capital at Saigon and was nominally under the authority of the former Vietnamese emperor, Bao Dai. Within 300 days of the signing of the accords, a demilitarized zone, or DMZ, was to be created by mutual withdrawal of forces north and south of the 17th parallel, and the transfer of any civilians who wished to leave either side was to be completed. Nationwide elections to decide the future of Vietnam, North and South, were to be held in 1956.

Accepting the de facto partition of Vietnam as unavoidable but still pledging to halt the spread of communism in Asia, U.S. President Dwight D. Eisenhower began a crash program of assistance to the State of Vietnam—or South Vietnam, as it was invariably called. The Saigon Military Mission, a covert operation to conduct psychological warfare and paramilitary activities in South Vietnam, was launched on June 1, 1954, under the command of U.S. Air Force Col. Edward Lansdale. At the same time, Viet Minh leaders, confidently expecting political disarray and unrest in the South, retained many of their political operatives and propagandists below the 17th parallel even as they withdrew their military forces to the North. Ngo Dinh Diem, the newly installed premier of South Vietnam, thus faced opposition not only from the communist regime in the North but also from the Viet Minh’s stay-behind political agents, armed religious sects in the South, and even subversive elements in his own army. Yet Diem had the full support of U.S. military advisers, who trained and reequipped his army along American lines and foiled coup plots by dissident officers. Operatives of the U.S. Central Intelligence Agency (CIA) bought off or intimidated Diem’s domestic opposition, and U.S. aid agencies helped him to keep his economy afloat and to resettle some 900,000 refugees who had fled the communist North.

By late 1955 Diem had consolidated his power in the South, defeating the remaining sect forces and arresting communist operatives who had surfaced in considerable numbers to prepare for the anticipated elections. Publicly opposed to the elections, Diem called for a referendum only in the South, and in October 1955 he declared himself president of the Republic of Vietnam. The North, not ready to start a new war and unable to induce its Chinese or Russian allies to act, could do little.

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